This invention relates to a process for obtaining a hermetic connection between a rigid tube or pipe and an apparatus. It also relates to a method of forming a connectable pipe end.
In installations for carrying hydraulic or pneumatic fluids under pressure, the rigid connection of the rigid tubes to different openings of the apparatus of the installation is generally obtained by means of a female screw or nut. The nut is retained on the tube or pipe by a collar which extends from the end of tube or pipe. The nut has an inwardly extending shoulder which abuts the collar of the tube when tube is connected making the female screw or nut a prisoner of the tube. A threaded nipple, forming a portion of and solid with the opening of the apparatus to which the tube is to be connected, threadedly receives the nut to join the tube to the apparatus. The frontal surface of the nipple, against which the face of the collar of the tube abuts, has a sealing joint, arranged in an annular throat to provide a sealed connection between the joined ends.
In prior art connections of this type, the collar of the tube is a beaten collar, that is, it is obtained by placing the end of a tube in a die and striking it with a succession of calibrated tools. The successive beating application of the tools to the tube progressively deforms the end of the tube until the desired collar shape is obtained. This is a time consuming and costly process.
This invention is intended not only to decrease the time of manufacture of such a connection, but also to reduce its cost.